USD for Maya 0.32 now supports Animation Curves for camera attributes in exports.

Support for Animation Curves for camera attributes
The USD Exporter now supports animation curves for camera attributes such as aperture and focal length.
Support for MaterialX documents
We've added support for MaterialX documents in the USD Exporter.
Updated USD lights
USD lights now use relevant shape size settings, ensuring accurate shape representation in the viewport.
USD Collection Widget improvements
We've improved the USD Collection Widget for better performance and usability.
New Python functions for USD Layer Editor
You can now use the new Python functions to get and set the selected layer in the USD Layer Editor.
See USD for Maya 0.32.0 Release Notes for other improvements and bug fixes.
To upgrade Maya USD, see Installation Instructions.
To get familiar with USD terminology, see USD terminology and composition.
To learn about the USD workflow, watch the tutorials on Maya Learning Channel.
For more information and to get involved with USD development, visit the official Autodesk Maya USD GitHub community.